Oil burning apparatus



April 10, 1934.

F. A. HEATH .OIL BURNING APPARATUS original lFiled Aug. vs. 1925INVENTOR ATTORNEY Patented Apr. 10, 1934 UNITED STATES '1,954,293 on..BURNING APPARATUS Forrest A.V Heath, Philadelphia, ra., mignr uhimself, Karl B. Segall, and Walter F. Tant,

Detroit, Mich. l

original application August s, 192s, semi No.

Divided and this application April 19,

1.928, Serial N0. 271,129 y 7 ciaims. (c1. 15a-i7) My present inventionrelates to oil burners of the so-called automatic type adapted to burnliquid fuel, particularly the heavier yor so-called fuel oils, and theconstruction is peculiarly adapted for converting ordinary coal burningfurnaces into oil furnaces although it will be evident that variousfeatures of the invention may be applied to other burners .which mayalso be adapted for other uses. This application is a division of mycopending application Ser. No. 47,709, filed August 3, 1925. Y

The apparatus in connection with which the present invention is shown'includes means for initially forming a crude, over-rich carburettedmixture of oil spray suspended in and projected with a relatively smallpercentage of primary air in combination with special homogenizing andpropelling means whereby the spray in this initial draft is atomizedand-intimately mixed with said initial air and also with some additionalprimary air and the Whole projected as a homogeneous fuel draft in closerelation to the main4 draft of air necessary for complete combustion.The'means for forming the initial spray in an air draft is shown asbeing ofthe centrifugal spray cup type and the cup is rotated at thespeeds required for centrifugal operation by a small electric motorwhich preferably is also utilized for driving the homogenizing andpropelling means.

An important feature of the present invention relates to means forsupplying oil to the centrifugal cup and according to a preferred formof the invention the feeding of the oil to the centrifugal cup iseffected by means ofA picker tubes arranged vertically and having attheir lower ends narrow integral extensions formed\by cutting awaytheftube, bending it horizontally through somewhat less than a quadrantof a circle and cutting the end to V-shape, the side walls of the Vbeing vertical, so that they tend to laterally deflect the oil in whichthey are normally submerged.- The forwardly presented upper surface ofthe pick acts to skim olf and deflect the oil upwardly. 'I'he rate atwhich the' oil is elevated varies approximately as the depth to whichthe deflecting surface is submerged in the oil. As the depth ofsubmergence of the tip is increased, the more there is of the uniformwidth portion ofthe pick? which is submerged and the -greater' is therate of oil elevation. Hence, for any given setting of the pick tubes,the amount or rate of oil supply can be gauged with greatest accuracy byraising orfl'owering the level cf the oil ,to increase or decrease thedepth of sub.

'centrifugal cup and the pickers.

mergence of the tip of the pick. Air is also carried up through thepickers and ,the outward movement of the air and oil'at the top of the`spray producing devices together with the motor are suspended from thecentral part of the hearth by a three-point suspension arrangement. Themotor is also connected with the spray cup and picker tube rotatingstructure by means of a flexible connection. One important feature ofthis form of support is that both the hearth and the oil atomizing partscan be adjusted both vertically and as to inclination. Furthermore, bysuspendingthe oil atomizing structure and the motor from the hearth the'vibrations of the running parts are not transmitted directly `to theiioor and not only is the vibration cut down but the .apparatus is verymuch quieter in operation. This adjustment is also important to positionthe oil well' so that the pickers will enter the oil to the same extentin all points around their path.

The above and other features and novel details of. my invention will bemore-fully understood from the following description in connection withthe accompanying drawing, in which Fig. l is a vertical axial sectionthrough the burner and a portion of the hearth in one form ofinstallation;

Fig. 2 is an axial sectional detail of one of th picker tubes 37 of Fig.1; and

Fig. 3 is a section on a smaller scale and taken o n the staggeredline3--3 of Fig. l.

The refractory hearth 10 is supported at its center by a circular plate11, which is supported in turn at its inner edge by a'platform member l2having an integrali upstanding iiange 13 defining a drainage groove 14,for draining off any oil that may leak through the joint o f therefractory hearth with its metal support 12. At the upper edge of theplatform member 12 there is a collar 15 throughsyhich projects shaft 1'6carrying 4the homogenizing rotor .17 having pro-` peller blades 18surrounding the outlet from the aov centrifugal spray cup 19, which isalso mounted on said shaft 16. As shown in Fig. 1, there is an annularpassage between the spray cup 19`and collar 15, not only for clearanceto permit rotation of the former, but also to provide for the main airdraft drawn into the furnace by chimney suction.

The platform member 12 is supported by leg sections 20 telescoped in legsections 21 and adjustably held by screws 21a. Preferably, there arethree legs to afford three-point support. Each legl section 21 hasscrewed into the lower end thereof an adjustable section 22 secured by alock nut 23 whereby the legs may be readily adjusted to true verticaleven though the floor of the ash pit be very uneven. The lower end ofeach member 22 is preferably headed as at 22a, and the head is cushionedby a rubber block 24 held by a metal clip 25 secured to the head 22a.The adjustable leg sections are held in fixed relation by a U-shapedcasting 2lb. The three-point support afforded by the telescoping legsections makes it easy to adjust them for proper support of the hearth10 through its supporting .platform member 12. l

Projecting through and concentric with th collar 15 is the centrifugalor carburetting spray cup 19 formedat the bottom with inlets 26 forsupplying the oil spray to be mixed with the air and projected from thetop of the cup at 27. The cup is formed with a central tubular member 28fitting the vertical'shaft at 29 and resting on an enlargement thereofas at 30. On top of thisy tubular projection is tted a disk 31 carryingradial fan blades 32. On disk 31 are clamped a cover member 33 whichcloses the whole top of the Icup and is dish shaped so that itsperipheral wall 33a. is approximately parallel with the lip portion ofthe cup, and a second cover member 33y fitted on top of 33. Obviously,the cover members 33 and 33 may be considered as parts of the cup 19.Disk 31 and covers 33 and 33 are clamped down on the top of the tubularmember 28 by an annular clamping collar 34 secured by a clamping nut 35.All of the parts may be sufliciently held against rotation on the shaft16 by the clamping action of nut 35, but I prefer to provide a key 36engaging clamping collar 34 and extending through 33', 33 and 31.

The bottom of the cup 19 is thickened down- Wardly to provide anadequate lateral bearing for the picker tubes 37 that extend downwardlytherethrough and are secured therein in any desired position of verticaladjustment by means of screws 38. Also integral with the bottom of thecup and outside of the downward extending picker tubes is a circulardepending lip 39 adapted to close the opening into a suitable oil Wellcasing 40. 'I'his casing is preferably provided with a plurality ofhorizontal diaphragms, such as 41 and 42, which clear the rotary closureor lip 39 and with it form a labyrinth facilitating down- Ward drainageof oil into the oil supply chamber or Well 43 and baffling escape of oilfrom said chamber to the outside. 'I'he depending annulus 44 servessimilarly to baffle splash and to damp Wave motion that may be set up bythe pickers when rapidly rotated to lift the oil. Rotation of the oil isdamped by radial ribs 45 projecting from the bottom of the oil reservoiralmost to the level of the normal surface of the oil.

The oil well 43 has a central cylindrical barrel 46 and the cup bearingshaft 16, 29 has a downward extension 47 which is journaled on suitablebearings, such as ball bearings, in said barrel.

For lubricating purposes the top and bottom of the barrel below thelower ball bearing and above the upper ball bearing are closed bysuitable pack,- ings such as shown in said co-pending application ofwhich this is a division. 'Ihe cavity is initially filled with bearinggrease and additional grease may be forced in at any time through duct48 in one of the ribs 45 by removing screw plug 49 and applying a greasegun.

Below the shaft and in alignment therewith is the electric motor 50,which may be of ordinary construction adapted to use alternating ordirect current, and designed to rotate a spray cup, pickers andhomogenizing propellers carried thereby at the required speed, which maybe as low as 1700 to 1800 revolutions per minute, for a model built on ascale which will make the extreme overall diameter of the homogenizer 8(Fig. 1) inches.

The armature shaft 51 of the motor 50 is detachably secured to the cupshaft by -a flexible coupling 52 which may comprise a block of elasticmaterial 53 through which the drive is applied. This exible coupling maybe the same as that disclosed in my said co-pending application.

The oil well structure and motor are supported in any suitable Way. Asshown in Fig. 1, the oil well has three-point support from the platformmember 12 by means of stud bolts 54, screwthreaded into 12 and passingthrough vertically apertured ears 55 which' are integral with andoutside of a drainage. gutter 56 which is integral with the oil well.Any desired position of vertical adjustment for the oil well, driveshaft and spray cup carried thereby may be fixed for each stud bolt 54by means of a lock nut 57, vertical displacement being prevented bythumb nut 58. In

the form shown the motor is secured by screws l 59 adjustably engaging adepending bracket 60 Wh'ch is secured to the bottom of the oil wellcasing by flanges 61 fitting against the same and secured thereto byscrews not shown. 'I'he vertical bracket member is stayed by deepflanges 62 and 63.

Oil is supplied through the bottom of the oil Well by pipe 64 and wasteoil in the collecting gutter 56 is drained voff through pipe 65. Itshould be understood that the supply of oil through the pipe 64 may becontrolled in any. suitable manner, for example, by a float-controlledvalve. The gutter 56 is in position to collect oil from the spray cupand also from the groove 14 which discharges throughA the duct 14a, butits main purpose is to collect oil that drains from the inclined hearthwhen the pilot light fails or for any other reason when oil is to bedischarged at a rate greatly in excess of the rate at which it is beingburned. In such cases the oll drains down the incline of the hearth andthrough the slots 15a in collar 15 and drips into the collecting gutter56,- whence it goes through p ipe 65 to a suitable control mechanismforming no part of my present invention. It is sufficient to say thatthis mechanism, accurately controls the level of the oil in the oil welland completely shuts off the supply 0f oil whenever there is excessdrainage through pipe 65.

The picker tubes 37 are preferably of the form shown in Fig. 2, thepicker at the lower end consisting of a narrow integral extension 37aformed by cutting away the tube, bending it horizontally throughsomething less than a quadrant of a lat proximately vertical, but thiswhile desirable is not essential. 'Ihe thin film of oil is skimmed offby reason of the fact hat the loil is stationary while the picker tubeis traveling circularly at high linear speed around a circle which maybe, say, 6 or 8 inches in diameter, driven by a motor which is rotated,say, 175,0 revolutions per minute.

Although the oil is mobile, it is held by inertia against the thrust ofthe picker and is deflected upwardly through the tube at high velocity.Air is also carried up in the same way and the upward movement of bothof them is facilitated by the fact that the tube is cut off at an angleon the rear side as shown at 37e. The effect is that by as much as thespeed of rotationof the upper end of the tube is greater than the airwithin the spray cup, by so much is there a suction effect applied atthe outlet. In this connection, it is to be remembered that an evengreater suction effect is applied by reason of the fact that the cupitself is a centrifugal blower, see fan blades 32, and tends to draw inair through each picker tube 37, as well as througluthe regular airinlet 26. Obviously also the picker is itself an air scoop, as well asan oil scoop.

The amount of oil supply can be gauged with greatest accuracy by gaugingthe depth of oil in the oil well, and one advantage in having ,thepicker cut away to a mere finger with its lower, ,oil skimming portionof approximately uniform width as shown in the drawing, is that theamount of o'1 lifted will be more nearly proportional to` `the depth ofthe oil. The amount of oil could also be varied by vertically adjustingthe picker tubes, but this is an undesirable way, since the oil level inthe well should be kept YVas near the top of the ribs 45 as ispracticable, thereby making the ribs as effective as possible inpreventing the pickersfrom imparting rotary motion tothe oil, it beingobviously desirable to minimize all disturbances of the oil and hold itstationary as against the scoop action of the pickers.

The spray thrown from the upper end of the picker tubes is subjected tocentrifugal fdrce tending to drive it through the air currents withintlie cup19 and in practiceimuch of it impinges on the side of the cupadjacent the outlet annulus.

Much of it, however, goes into suspension in the.

primary a'r,` which is discharged through the same outlet by centrifugalforce which is assisted by the fan blades 32, although the latter may beomitted if desired. The richly'carburetted mix'- ture is dischargedupwardly. against the horizontal baflie a-nnulus 66 of the cover plate33, and the adjacent bases of the inner propeller blades 18a.

Thev unsuspended oil creeps by the walls of the cup by centrifugal forceand is projected in minute drops against the intermediate portions ofsaid blades. This is on a level below the primarilyn carburetted air andin the path of the main air draft coming up through` the collar 15 -at ahigh angle to the horizontally projected liquid. This tends to driveupward the minute drops that have been shattered by impact with theinner faces of the blades 18a toward the baille plate 66 and those thathave been caught by the outer surface of blades 18a upward towards thehorizontal or baffle annulus 66a of the outer propeller.

vAs a result'of the baffling, eddying, mixing and shattering thusproduced, a desired amount of additional primary 'air comes incorporatedin homogenous mixturewith a'flnely atomized and partially vaporizedliquid which is propelled outward. A large part of the upwardmaingdraft,

however, is deflected, part being driven upward by the propeller bladesover the hearth as an air stratum, merging into a richly carburettedstratum, another part eddying back and being again projected upward bythe injector -action of the upper part of the draft stream.

The radially projected stratum has its upward surface exposed to theproducts of combustion within the furnace chamber and, as pointed out,in said co-pending application of which this is a division, entraine andmerges with both the upper and lower sheet as it accentuates byspreading along the divergent lines of the circle. Fur-` ther disclosureof the action of the homogenizing propeller may be found in said priorapplication Ser. No. 47,709 and inasmuch as the features of thehomogenizing propeller are not claimeddn the present applibation,further discussion thereof is unnecessary.

It should be understood that my invention is not limited to the detailsof construction above described.

I claim: i 1. Fuel metering apparatus, including an oil well and a motordriven spray cup, in combination with means including a picker fingercarried by the cup, extending downwardly, and curving forwardly to skima film from the surface of the oil in the well and discharge it into theair inthe cup, said finger being formed with V- shaped tip, theforwardly presented surfaces thereof being disposed approximatelyvertically to have a lateral plowing effect onthe oil.

2. Fuel metering apparatus, including an oil Well and a motor drivenspray cup, in combination with means including a picker finger .carriedby the cup,. extending downwardly, and curving forwardly to skim a filmfrom the surface of theoil in the well and discharge it into the air inthe cup, the oil skimming portions of said finger near and above thepoint of engagement with the surface of the oil being of approximatelyuniform width.

3. Fuel metering apparatus, including an il skimming portions of saidnger near and above the point of engagement with the surface of the oilbeing of approximately uniform width.

4. .Fuel metering apparatus, including an oil well and a motor drivenspray cup, in combination with picker tubes extending through the bottomof the cup, eccentric to and approximately parallel with the axisthereof, each carrying at its lower end a downwardly extending finger,curved forwardly in the direction of rotation, in position to skim thesurface of the oil in said well and deflect it upward into said tubes,said tubes beingentirely open at the upper end and cut diagonally so asto afford free rearward and upward exit to the Voil dischargedtherethrough.

K 5. Fuel metering'apparatus, including an' oil well and a motor drivenspray cup, in combination with pickerv tubes extending through thebottom of the cup, eccentric to andapproximately4 the direction ofrotation, in'

position to skim the surface of the oil in said well and deect it upwardinto said tubes, said tubes being entirely open at the upper'end, theoil skimming portion of said fingers near and above the point ofengagement with the surface of the oil being of approximately uniformwidth.

6. Fuel metering apparatus, including an oil well and a motor drivenspray cup, in combination with picker tubes extending through the bottomof the cup, eccentric to and approximately parallel with the axisthereof, each carrying at its lower end a downwardly extending nger,curved forwardly in the direction of rotation, in position to skim thesurface of the oil in said well and deect it upward into said tubes saidfingers being formed with V`shaped tips, the forwardly presentedsurfaces thereof being disposed approximately vertically to have alateral plowing effect on the oil.

7. Fuel metering apparatus, including an oil :well and a motor drivenrotor for centrifugally spraying oil, in combination with meansincluding a picker finger carried by said rotor, extending downwardlyand curving forwardly to skim a film of desired depth from the surfaceof the deflect the oil Without substantial lifting effectv thereon.

FORREST A. HEATH.

